In recent years, imaging systems have emerged that use a pixel array to sense temporal changes in contrast and to asynchronously report the temporal changes in contrast together with a time stamp. For instance, a completely static scene produces no temporal changes in contrast for the pixels in the pixel array and none of the pixels reports a temporal change in contrast from a first time to a second time. Accordingly, no report is generated unless there is a change in contrast for the pixel, which reduces power consumption.
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